Network Working Group Donald Eastlake 3rd INTERNET-DRAFT Motorola Laboratories Updates: RFC 2153 Intended Status: Best Current Practice Expires: February 2008 August 2007 IANA Ethernet Considerations ---- ------- --------------- Status of This Document By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. This document is intended to become a Best Current Practice. Distribution of this document is unlimited. Comments should be sent to the author or the IESG . Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html Abstract Some IETF protocols make use of IEEE 802 frame formats and parameters. This document specifies IANA considerations for code points under the IANA OUI (Organizationally Unique Identifier). It also lists and discusses other IETF 802 parameters. D. Eastlake [Page 1] INTERNET-DRAFT IANA Ethernet Considerations Table of Contents Status of This Document....................................1 Abstract...................................................1 Table of Contents..........................................2 1. Introduction............................................3 1.1 Notation in This Document..............................3 1.2 The IEEE Registration Authority........................3 1.2.1 The IANA OUI.........................................3 2. IEEE 802 Address Parameters.............................4 2.1 EUI-48 MAC Addresses and OUIs..........................4 2.2. EUI-48 Allocations under the IANA OUI.................4 2.2.1 EUI-48 IANA Allocation Considerations................5 2.3 EUI-64 Identifier Allocations..........................6 2.4 Other IETF Used EUI-48 Addresses.......................7 2.4.1 Allocation in the 'CF Series'........................7 3. IEEE 802 Protocol Parameters............................8 3.1 802 Protocol Allocation Under the IANA OUI.............9 4. Exhaustion.............................................10 5. IANA Considerations....................................11 6. Security Considerations................................11 7. Normative References...................................12 8. Informative References.................................12 Template Annex............................................13 EUI-48 Identifier or Identifier Block Template............13 5-octet Ethernet Protocol Identifier Template.............14 Ethertypes Annex..........................................15 Some IETF Ethertypes......................................15 Some IEEE 802 Ethertypes..................................15 Disclaimer................................................16 Additional IPR Provisions.................................16 Author's Address..........................................17 Expiration and File Name..................................17 D. Eastlake [Page 2] INTERNET-DRAFT IANA Ethernet Considerations 1. Introduction Some IETF protocols make use of Ethernet or other [IEEE] 802 related communications frame formats and parameters [IEEE802]. These include addresses and protocol identifiers. This document specifies IANA considerations for the allocation of code points under the IANA OUI. It also lists and discusses other IETF use of Ethernet code points not under the IANA OUI. 1.1 Notation in This Document This document uses what is called Hexadecimal Notation. Each octet (that is, 8-bit byte) is represented by two hexadecimal digits giving the value of the octet as an unsigned integer and successive octets are separated by a hyphen. This document consistently uses IETF bit ordering although, for example, the physical order of bit transmission within an octet on an 802.3 link is from the lowest order bit to the highest order bit, the reverse. In this document: "IAB" standards for Individual Address Block, not for Internet Architecture Board; "MAC" standard for Media Access Control, not for Message Authentication Code; and "OUI" stands for Organizationally Unique Identifier. 1.2 The IEEE Registration Authority Originally the responsibility of Xerox Corporation, the registration authority for IEEE 802 parameters is now the IEEE Registration Authority, available on the web at http://standards.ieee.org/regauth/. Application may be made to that authority for parameters. Fees and other requirements may apply although fees are commonly waived for applications from standards development organizations. A list of allocated OUIs and IABs and their holders is downloadable from the IEEE Registration Authority site. 1.2.1 The IANA OUI The OUI 00-00-5E has been allocated to IANA. D. Eastlake [Page 3] INTERNET-DRAFT IANA Ethernet Considerations 2. IEEE 802 Address Parameters Section 2.1 below discuses EUI-48 MAC addresses, their relationship to OUIs, and allocations under the IANA OUI. 2.1 EUI-48 MAC Addresses and OUIs IEEE 48-bit MAC "addresses" are the most commonly used Ethernet device identifiers and are also called EUI-48 (Extended Unique Identifier 48) identifiers. They are structured into an initial 3 octet OUI (Organizationally Unique Identifier) and an additional 3 octets of address assigned by the OUI holder. In addition, for organizations not requiring 3 octets worth of identifiers, the IEEE makes IABs (Individual Address Blocks) where the first 4 1/2 octets (36 bits) are allocated giving the holder of the IAB 1 1/2 octets (12 bits) they can control. [802] Two bits within the initial 3 bytes have special significance, the Group bit (01-00-00) and the Local bit (02-00-00). OUIs are allocated with the Local bit off and the Group bit unspecified. OUI holders may use them to construction multicast addresses by turning on the Group bit or unicast addresses by leaving the Group bit zero. For globally unique EUI-48 identifiers allocated by an OUI owner, the Local bit is zero. If the Local bit is a one, the identifier is normally considered a local identifier under the control of the local network administrator. The holder of an OUI (or IAB) has no special authority over EUI-48 identifiers whose first three (or 4 1/2) octets correspond to their OUI (or IAB) if the Local bit on. 2.2. EUI-48 Allocations under the IANA OUI The OUI 00-00-5E has been assigned to IANA as described in Section 1.2.1 above. This includes 2**24 EUI-48 multicast addresses from 01-00-5E-00-00-00 to 01-00-5E-FF-FF-FF and 2**24 EUI-48 unicast addresses from 00-00-5E-00-00-00 to 00-00-5E-FF-FF-FF. Of these EUI-48 identifiers, the following allocations have been made thus far: o The 2**23 multicast addresses from 01-00-5E-00-00-00 through 01-00-5E-7F-FF-FF have been allocated form IPv4 multicast [RFC1112]. D. Eastlake [Page 4] INTERNET-DRAFT IANA Ethernet Considerations o The 2**8 unicast addresses from 00-00-5E-00-00-00 through 00-00-5E-00-00-FF are reserved and require IESG approval for allocation. o The 2**8 unicast addresses from 00-00-5E-00-01-00 through 00-00-5E-00-01-FF have been allocated for the Virtual Router Redundancy Protocol (VRRP) [RFC3768]. 2.2.1 EUI-48 IANA Allocation Considerations IANA EUI-48 allocations under the current or a future IANA OUI (see Section 4.) must meeting the following requirements: o must be for standards purposes, o must be for a block of a power of two addresses starting at a boundary which is an equal or greater power of two, including the allocation of one (2**0) identifier, o are not to be used to evade the requirement for vendors to obtain their own block of addresses from the IEEE, and o must be documented in an internet-draft or RFC. In addition, Expert or IESG approval must be obtained as listed below: Small allocations of 1, 2, 4, 8, or 16 addresses require the approval of any one member of the pool of Experts using the procedure specified in Section 5 below. Medium sized allocations of 32, 64, 128, or 256 addresses require the approval of any two members of the pool of Experts using the procedure specified in Section 5 below. Allocations of any size, including 512 or more addresses, may be made with IESG approval. To simplify record keeping, all future allocations of 256 or less addresses shall have the Group bit unspecified, that is, shall be allocations of parallel equal size blocks of multicast and unicast addresses, even if one of these two types is not needed for the proposed use. The only exception is that requests for unicast only address blocks of any size that are available may be allocated out of the remaining addresses in the large unicast range from 00-00-5E-00-02-00 to 00-00-5E-7F-FF-FF. D. Eastlake [Page 5] INTERNET-DRAFT IANA Ethernet Considerations 2.3 EUI-64 Identifier Allocations IEEE also defines a system of 64-bit EUIs. Uptake of EUI-64 identifiers has been limited. They are currently used by the following IEEE standards: o IEEE 1394 (also known as FireWire and i.Link), o IEEE 802.15.4 (also known as ZigBee). They are also used to form local use some IPv6 addresses ([RFC3513], section 2.5.1 and Appendix A). Modified EUI-64 identifiers under an OUI are formed by adding a 5-octet (40-bit) extension as illustrated below for the IANA OUI, where aa-bb-cc-dd-ee is the extension. [RFC4214] 02-00-5E-aa-bb-cc-dd-ee The first octet is show as 02 rather than 00 because, in Modified EUI-64 identifiers, the sense of the local/global bit is inverted compared with EUI-48 identifiers. It is the globally unique values (universal scope) under the IANA OUI that have the 02 bit on while those with this bit off are locally assigned and out of scope for IANA allocation. As with EUI-48 identifiers, the 01 bit on would indicate a group address. When the first two octets of the extension are FF-FE, the remainder of the extension is a 24 bit vendor-supplied ID as follows: 02-00-5E-FF-FE-yy-yy-yy where yy-yy-yy is the vendor-supplied ID. [[Since "vendor" usually means the holder of an OUI, does this mean that a use for which the EUI-48 00-00-5E-yy-yy-yy is allocated automatically also has the EUI-64 of 02-00-5E-FF-FE-yy-yy-yy?]] Certain EUI-64 identifiers under the IANA OUI are reserved for holders of IPv4 addresses as follows: 02-00-5E-FE-xx-xx-xx-xx where xx-xx-xx-xx is a 32-bit IPv4 address. [[So, should there be a way for IANA to allocate Modified EUI-64 addresses of the form 00-00-5E-z1-zz-zz-zz-zz where "z1" is some set of octet values less than 0xFE ??]] D. Eastlake [Page 6] INTERNET-DRAFT IANA Ethernet Considerations 2.4 Other IETF Used EUI-48 Addresses All EUI-48 multicast addresses prefixed "33-33", that is the 2**32 multicast MAC addresses in the range from 33-33-00-00-00-00 to 33-33-FF-FF-FF-FF, have been adopted by the IETF for global IPv6 multicast [RFC2464]. These addresses all have the Group bit (the bottom bit of the first byte) on as is required to work properly with existing hardware as a multicast address; however, they also have the Local bit on; nevertheless, they are used for this global purpose. (Historical note: It was the custom during IPv6 design to use "3" for example or unknown values and 3333 is the street address number of Xerox PARC (Palo Alto Research Center). Ethernet was originally designed by Digital Equipment Corporation, Intel Corporation, and Xerox Corporation. The early Ethernet protocol has sometimes been known as "DIX" Ethernet.) All "OUIs" prefixed "CF", that is, "OUIs" from CF-00-00 to CF-FF-FF were declared by Information RFC [RFC2153] to be available to software vendors when allocated by IANA for use in PPP [RFC1661] or for other uses where an IEEE allocation is "inappropriate". These "OUIs" have both the Group and Local bits on. The Group bit, or "multicast" bit, is meaningless in PPP. To quote [RFC2153]: "The 'CF0000' series was arbitrarily chosen to match the PPP NLPID 'CF', as a matter of mnemonic convenience." "OUI" CF-00-00 is reserved and IANA lists multicast address CF-00-00-00-00-00 as used for Ethernet loopback tests. 2.4.1 Allocation in the 'CF Series' In over a decade of availability, only a handful of "OUIs" in the 'CF Series' has been allocated. (See htto://www.iana.org under both Ethernet Parameters and PPP Parameters.) Use of these addresses based on IETF allocation is deprecated. IANA is directed not to allocate any further "OUIs" in the 'CF Series'. D. Eastlake [Page 7] INTERNET-DRAFT IANA Ethernet Considerations 3. IEEE 802 Protocol Parameters 802 Protocol parameters provide a means of indicating the contents of a frame, for example that its contents is IPv4 or IPv6. The concept has been extended for the labeling of "tags". A tag in this sense is a prefix whose type is identified by an Ethertype and which is then followed by another tag or by an Ethertype or LSAPs protocol indicator for the the "main" body of the frame, as described below. Traditionally in the [802] world, tags are fixed length and do not include any encoding of their own length. Thus anything which is processing a frame can not, in general, safely process anything in the frame past an Ethertype it does not understand. An example is the Q-tag [802.1Q] which provides VLAN and priority information for a frame. There are two types of protocol identifier parameters that can occur in Ethernet frames after the initial EUI-48 destination and source identifiers: Ethertypes: These are 16 bit quantities appearing the an initial two octets which, when considered as an unsigned integer, are equal to or larger than 0x0600. LSAPs: These are 8 bit protocol identifiers which occur in pairs immediately after a 16 bit (two octet) remaining frame length which, when considered as an unsigned integer, is less than 0x5DC. LSAPs (Local Subnet Access Points) occur in pairs where one is intended to indicate the source protocol and one the destination protocol, although thus far no significant use where the two are different has been found. Neither Ethertypes nor LSAPs are allocated by IANA but by the IEEE Registration authority (see Section 1.2 above and the Ethertype Annex below). However, both LSAPs and Ethernets have extension mechanisms so that they can be used with five byte Ethernet protocol identifiers allocated by IANA under the IANA OUI. When using the IEEE 802 LLC format (SNAP) [802] for a frame, an OUI based protocol identifier can be expressed as follows: xx-xx-AA-AA-03-yy-yy-yy-zz-zz where xx-xx is the frame length and, as above, must be small enough not to be confused with an Ethertype, "AA" is the LSAP which indicates this use and is sometimes referred to as the SNAP SAP, "03" is the LLC control octet indicating datagram service, yy-yy-yy is an OUI, and zz-zz is a protocol number, under that OUI, allocated by the OUI owner. The odd five byte length for such OUI based protocol identifiers was chose so that, with the LLC control byte ("03"), the result is 16 bit aligned. D. Eastlake [Page 8] INTERNET-DRAFT IANA Ethernet Considerations When using an Ethertype to indicate the main type for a frame body, the special "OUI Extended Ethertype" 88-B7 is available. Using this Ethertype, a frame body can being with 88-B7-yy-yy-yy-zz-zz where yy-yy-yy, zz-zz, and the five octet combination of y's and z's has the same meaning as in the SNAP format described above. It is also possible, within the SNAP format, to use an arbitrary Ethertype. This is done by putting the Ethertype as the zz-zz field about after an all zeros OUI (00-00-00). This would look like xx-xx-AA-AA-03-00-00-00-zz-zz where zz-zz was the Ethertype. (Note that, at this point, the 802 protocol syntax facilities are sufficiently powerful that they could be chained indefinitely. Whether support for such chaining is generally required is not clear but [802] requires support for xx-xx-AA-AA-03-00-00-00-88-B7-yy-yy-yy-zz-zz even though this could be more efficiently expressed by simply pinching out the "00-00-00-88-B7" in the middle.) As well as appearing to label frame contents, 802 Protocol types appear within NBMA Next Hop Resolution Protocol [RFC2332] messages which has provisions for both two octet Ethertypes and OUI based protocol types. 3.1 802 Protocol Allocation Under the IANA OUI Two octet protocol numbers under the IANA OUI are available for standards use, as in xx-xx-AA-AA-03-00-00-5E-zz-zz A number of such allocations have been made out of the 2**16 available from 00-00-5E-00-00 to 00-00-5E-FF-FF (see http://www.iana.org). New allocations of a SNAP SAP protocol (zz-zz) number under the IANA OUI requires approval of two Experts from the pool and using the procedure specified in Section 5 below. Such protocol numbers are not to be allocated for any protocol that has an Ethertype because that can be expressed in this SNAP SAP format by putting an all zeros "OUI" before the Ethertype. D. Eastlake [Page 9] INTERNET-DRAFT IANA Ethernet Considerations 4. Exhaustion When the available space for either multicast or unicast addresses under OUI 00-00-5E have been 90% or more exhausted, IANA should request an additional OUI from the IEEE Registration Authority (see Section 1.2) for further IANA allocation use. D. Eastlake [Page 10] INTERNET-DRAFT IANA Ethernet Considerations 5. IANA Considerations The entirety of this document concerns IANA Considerations for the allocation of Ethernet parameters. The Expert Pool referred to in this document shall consist of all voting members of the IAB and IESG. While finite, the universe of numbers from which these allocations being made is felt to be sufficiently large that the requirements given in this document and the Expert's good judgment are considered sufficient guidance. The procedure for Expert approval is that the applicant completes the appropriate Template from the Template Annex below and sends it to IANA. The Template includes a suggested Expert or Experts from the pool. IANA contacts one or two of the suggested experts, depending on how many approvals are required for the allocation requested, and obtains their opinion. If, within 30 days, IANA receives approvals from the Expert or Experts and code points are available, IANA will make the requested allocation. Otherwise, the application will be denied. A wise applicant will have discussed their application in advance with the person or persons from the pool that they suggest to IANA as Exerts. 6. Security Considerations This document is concerned with IANA allocation of parameters under the IETF OUI and is not directly concerned with security. D. Eastlake [Page 11] INTERNET-DRAFT IANA Ethernet Considerations 7. Normative References [802] "IEEE Standard for Local and Metropolitan Area Networks: Overview and Architecture", IEEE 802-2001, 8 March 2002. "IEEE Standard for Local and Metropolitan Area Networks: Overview and Architecture / Amendment 1: Ethertypes for Prototype and Vendor-Specific Protocol Development", IEEE 802a-2003, 18 September 2003. [RFC1112] Deering, S., "Host Extensions for IP Multicasting", STD 5, RFC 1112, Stanford University, August 1989. [RFC2464] Crawford, M., "Transmission of IPv6 Packets over Ethernet Networks", RFC 2464, December 1998. [RFC3513] Hinden, R. and S. Deering, "Internet Protocol Version 6 (IPv6) Addressing Architecture", RFC 3513, April 2003. 8. Informative References [802.1Q] "IEEE Standard for Local and metropolitan area networks / Virtual Bridged Local Area Networks", 802.1Q-2005, 19 May 2006. [IEEE] Institute of Electrical and Electronics Engineers . [IEEE802] IEEE 802 LAN/MAN Standards Committee (Local Area Network / Metropolitan Area Network) . [RFC1661] Simpson, W., "The Point-to-Point Protocol (PPP)", STD 51, RFC 1661, July 1994. [RFC2153] Simpson, W., "PPP Vendor Extensions", RFC 2153, May 1997. [RFC2332] Luciani, J., Katz, D., Piscitello, D., Cole, B., and N. Doraswamy, "NBMA Next Hop Resolution Protocol (NHRP)", RFC 2332, April 1998. [RFC3768] Hinden, R., "Virtual Router Redundancy Protocol (VRRP)", RFC 3768, April 2004. [RFC4214] Templin, F., Gleeson, T., Talwar, M., and D. Thaler, "Intra-Site Automatic Tunnel Addressing Protocol (ISATAP)", RFC 4214, October 2005. D. Eastlake [Page 12] INTERNET-DRAFT IANA Ethernet Considerations Template Annex This annex provides the specific templates for IANA allocations of parameter types specified in this document. Explanatory words in parenthesis in the templates below may be deleted in a completed template as submitted to IANA. EUI-48 Identifier or Identifier Block Template Applicant Name: Applicant Email: Applicant Telephone: (starting with country code) Use Name: (brief name of Parameter use such as "foo Protocol") Document: (ID or RFC specifying use to which the identifier or block of identifiers will be put) Size of Block requested: (must be a power of two sized block) Specify multicast, unicast, or both: Suggested Experts (maximum of three) to approve the allocation and judge that it meets the criterion in RFC TBD, Section 2.2.1: D. Eastlake [Page 13] INTERNET-DRAFT IANA Ethernet Considerations 5-octet Ethernet Protocol Identifier Template Applicant Name: Applicant Email: Applicant Telephone: (starting with country code) Use Name: (brief name of Parameter use such as "foo Protocol") Document: (ID or RFC specifying use to which the protocol identifier will be put) Suggested Experts (maximum of three) to approve the allocation and judge that it meets the criterion in RFC TBD: D. Eastlake [Page 14] INTERNET-DRAFT IANA Ethernet Considerations Ethertypes Annex This annex lists some Ethertypes used for IETF Protocols or by IEEE 802. See section 3 above. Some IETF Ethertypes 0x0800 Internet Protocol Version 4 (IPv4) 0x0806 Address Resolution Protocol (ARP) 0x8035 Reverse Address Resolution Protocol (RARP) 0x86DD Internet Protocol Version 6 (IPv6) 0x8847 MPLS unicast 0x8848 MPLS multicast 0x8863 PPP over Ethernet (PPPoE) Discovery Stage 0x8864 PPP over Ethernet (PPPoE) Session Stage Some IEEE 802 Ethertypes 0x8100 IEEE Std 802.1Q - Customer VLAN Tag Type (C-Tag, formerly called the Q-Tag) 0x888e IEEE Std 802.1X - Port-based network access control 0x88a8 IEEE Std 802.1Q - Service VLAN tag identifier (S-Tag) 0x88b5 IEEE Std 802 - Local Experimental Ethertype 0x88b6 IEEE Std 802 - Local Experimental Ethertype 0x88b7 IEEE Std 802 - OUI Extended Ethertype 0x88c7 IEEE Std 802.11i Pre-Authentication 0x88cc IEEE Std 802.1AB Link Layer Discovery Protocol (LLDP) 0x88f6 IEEE Std 802.1Q - Multiple Multicast Registration Protocol (MMRP) D. Eastlake [Page 15] INTERNET-DRAFT IANA Ethernet Considerations Disclaimer This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Additional IPR Provisions The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf- ipr@ietf.org. Copyright (C) The IETF Trust (2007). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. D. Eastlake [Page 16] INTERNET-DRAFT IANA Ethernet Considerations Author's Address Donald E. Eastlake 3rd Motorola Laboratories 111 Locke Drive Marlborough, MA 01752 email: Donald.Eastlake@motorola.com Expiration and File Name This draft expires in February 2008. Its file name is draft-eastlake-ethernet-iana-considerations-01.txt. D. Eastlake [Page 17]